Hot beverages (e.g., coffee, tea, hot chocolate, and the like) can present a handling problem to the consumer when dispensed into paperboard drink cups. That is, paperboard drink cups typically do not inherently provide sufficient thermal insulation properties when filled with hot beverages. As a result, an uncomfortable amount of the heat is transferred from the beverage contained in the drink cup to the consumer's hand resulting in some handling difficulty during beverage consumption.
In order to minimize such discomfort for customers, many retailers of hot beverages have resorted to using at least a pair of nested drink cups (so-called "double-cupping") so that the outer drink cup provides some degree of thermal insulation for the hot beverage contained by the inner drink cup. Such a precautionary technique, however, results in increased cup costs for the beverage retailer.
Other alternatives have also been proposed, such as cup sleeves disclosed in U.S. Pat. Nos. 3,908,523 to Shikaya, 5,205,473 to Coffin, Sr. and 5,222,656 to Carlson. The Shikaya '523 and Coffin, Sr. '473 patents each suggest providing thermal insulating sleeves for beverage cups having generally longitudinally oriented corrugations. The Carlson '656 patent suggests forming a tubular insulating sleeve from a felt-like material.
Recently, a paperboard sleeve has been offered for sale by Java Jacket of Portland, Oreg. The Java Jacket paperboard sleeve is an arcuate section of relatively heavy weight paperboard whose surfaces have been impressioned with rows of off-set dimples between which is formed a series of raised reliefs. Opposed slits at each end of the arcuate section allow the ends to be interlocked so that the sleeve may be held in position around the exterior of a paperboard container.